The elephant in the room: Is everything you see on an x-ray relevant?

Recent 'tongue in cheek' research which has been reported in a Washington Post blog recently has caused a lot of questions to be raised concerning inattention blindness, which could cause concern unless you understand the underlying psychology.

Here's a CT scan:

During psychology lectures at Med School, you may have encountered the basketball bouncing students in front of a bank of elevators where you were asked to count the number of passes the basketball made from the player wearing the white T shirt, while a gorilla ran between the students. (Even if you did watch it before, you can re-watch the video on the Washington Post blog).

The recent study asked radiologists to identify and count how many nodules are present in the lungs on a regular CT thorax. If you look at the image you may see a gorilla waving his arms about. As a radiologist, I see the anatomy in the background, the chambers of the heart and mediastinum, but nothing there out of the ordinary.

As radiologists, we are looking for pathology, but also report pathological findings that are unexpected. The clinical history of a patient is very important for us in interpretation of imaging examinations, as we need to answer the question you are asking, but have to be careful we do not miss anything else of serious import. As we do not see any other pathology, we would not expect to find a gorilla in the chest, so our brains can pass over distracting findings.

The other psychological issue is the satisfaction of search, where we can see the expected pathology, but may miss the other cancer if we do not carefully and systematically look through the images.

So the main thing to learn from this is that your training should always keep you alert, not just to expected happening, but to not discount the unexpected, then many lives will be saved as a result of your attention to detail.

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Thanks for this Chris. I recently read a review of this research on the health section of the [BBC News Health Website...](http://www.bbc.co.uk/news/health-21466529 "")
It is amazing to think that the brain can filter out information that is not though

More Blog Posts on Meducation

It’s quick, it’s easy and we’ve all done it. Don’t blush, whether it’s at our leisure or behind the consultant’s back we can confess to having used the world’s sixth most popular website. You might have seen it, sitting pride of place on the podium of practically any Google result page. Of course, it’s the tell tale sign of one of Web 2.0’s speediest and most successful offspring, Wikipedia.
Now for fear of patronizing a generation who have sucked on the teat of this resource since its fledgling years, the formalities will remain delightfully short. Wikipedia is the free, multilingual, online encyclopedia, which harnesses the collective intelligence of the world’s internet users to produce a collaboratively written and openly modifiable body of knowledge. The technology it runs on is a highly flexible web application called wiki. It is open-source software; hence the explosion of wiki sites all united under the banner of combined authorship. Anyone with internet access can edit the content and do so with relative anonymity. It would be unthinkable that a source, which does not prioritize the fidelity of its content, could possibly play a role in medical education. How ironic it seems that medical students can waste hours pondering which textbook to swear their allegiance for the forthcoming rotation, yet not spare a second thought typing their next medical query into Wikipedia. Evidently it has carved itself a niche and not just among medical students, but healthcare professionals as well. According to a small qualitative study published in the International Journal of Medical Informatics, 70% of their sample, which comprised of graduates from London medical schools currently at FY2 and ST1 level, used Wikipedia in a given week for ‘clinical purposes’. These ranged from general background reading to double checking a differential and looking up medications.
We are so ensnared by the allure of instantaneous enlightenment; it’s somewhat comparable to relieving an itch. "Just Google it..." is common parlance. We need that quick fix. When the consultant asks about his or her favourite eponymous syndrome or you’re a little short on ammunition before a tutorial, the breadth and ease-of-use offered by a service accessible from our phones is a clandestine escape.
The concept of Wikipedia, the idea that its articles are in a way living bodies because of the continual editing process, is its strength. Conversely textbooks are to a degree outmoded by the time they reach their publication date. While I commend the contributors of Wikipedia for at least trying to bolster their pages with references to high impact journals, it does not soften the fact that the authorship is unverifiable. Visitors, lay people, registered members under some less than flattering pseudonyms such as Epicgenius and Mean as custard, don’t impart the sense of credibility students (or for that matter patients)expect from an encyclopedia. Since the prestige of direct authorship if off the cards, it does beg the question of what is their motivation and I’m afraid ‘the pursuit of knowledge and improving humanity’s lot' is the quaint response. There is a distinct lack of transparency. It has become a playground where a contributor can impress his/her particular theory regarding a controversial subject unchallenged. Considering there is no direct ownership of the article, who then has the authority to curate the multiple theories on offer and portray a balanced view? Does an edit war ensue? It is not unheard of for drug representatives to tailor articles detailing their product and erase the less pleasant side-effects. Obviously Wikipedia is not unguarded, defences are in place and there is such a thing as quality control. Recent changes will come under the scrutiny of more established editors, pages that are particularly prone to vandalism are vetted and there are a special breed of editors called administrators, who uphold a custodial post, blocking and banishing rebellious editors. A study featured in the First Monday journal put Wikipedia to the test by deliberately slipping minor errors into the entries of past philosophers. Within 48 hours half of these errors had been addressed. Evidently, the service has the potential to improve over time; provided there is a pool of committed and qualified editors.
Wikiproject Medicine is such a group of trusted editors composed primarily of doctors, medical students, nurses, clinical scientists and patients. Since 2004, its two hundred or so participants have graded an excess of 25,000 health-related articles according to quality parameters not dissimilar to peer review. However, the vast majority of articles are in a state of intermediate quality, somewhere between a stub and featured article. Having some degree of professional input towards a service as far reaching as Wikipedia will no doubt have an impact on global health, particularly in developing countries where internet access is considered a luxury.
March this year saw the medical pages of the English Wikipedia reach a lofty 249,386,264 hits. Its ubiquity is enviable; it maintains a commanding lead over competing medical websites. The accessibility of this information has catapulted Wikipedia far beyond its scope as a humble encyclopedia and into a medical resource. Patients arrive to clinics armed with the printouts. As future doctors we will have to be just that one step ahead, to recognise the limitations of a source that does not put a premium on provenance but is nevertheless the current public health tool of choice.
Illustrator Edward Wong
This blog post is a reproduction of an article published in the Medical Student Newspaper, November 2013 issue.

So you're sitting in a bus when you see a baby smile sunnily and gurgle at his mother. Your automatic response? You smile too. You're jogging in the park, when you see a guy trip over his shoelaces and fall while running. Your knee jerk reaction? You wince. Even though you're completely fine and unscathed yourself. Or, to give a more dramatic example; you're watching Titanic for the umpteenth time and as you witness Jack and Rose's final moments together, you automatically reach for a tissue and wipe your tears in whole hearted sympathy ( and maybe blow your nose loudly, if you're an unattractive crier like yours truly).
And here the question arises- why? Why do we experience the above mentioned responses to situations that have nothing to do with us directly? As mere passive observers, what makes us respond at gut level to someone else's happiness or pain, delight or excitement, disgust or fear? In other words, where is this instinctive response to other people's feelings and actions that we call empathy coming from?
Science believes it may have discovered the answer- mirror neurons.
In the early 1990s, a group of scientists (I won't bore you with the details of who, when and where) were performing experiments on a bunch of macaque monkeys, using electrodes attached to their brains. Quite by accident, it was discovered that when the monkey saw a scientist holding up a peanut, it fired off the same motor neurons in its brain that would fire when the monkey held up a peanut itself. And that wasn't all. Interestingly, they also found that these motor neurons were very specific in their actions. A mirror neuron that fired when the monkey grasped a peanut would also fire only when the experimenter grasped a peanut, while a neuron that fired when the monkey put a peanut in its mouth would also fire only when the experimenter put a peanut in his own mouth. These motor neurons came to be dubbed as 'mirror neurons'.
It was a small leap from monkeys to humans. And with the discovery of a similar, if not identical mirror neuron system in humans, the studies, hypotheses and theories continue to build. The strange thing is that mirror neurons seem specially designed to respond to actions with clear goals- whether these actions reach us through sight, sound, smell etc, it doesn't matter. A quick example- the same mirror neurons will fire when we hop on one leg, see someone hopping, hear someone hopping or hear or read the word 'hop'. But they will NOT respond to meaningless gestures, random or pointless sounds etc. Instead they may well be understanding the intentions behind the related action. This has led to a very important hypothesis- the 'action understanding' ability of mirror neurons.
Before the discovery of mirror neurons, scientists believed our ability to understand each other, to interpret and respond to another's feeling or actions was the result of a logical thought process and deduction. However, if this 'action understanding' hypothesis is proved right, then it would mean that we respond to each other by feeling, instead of thinking. For instance, if someone smiles at you, it automatically fires up your mirror neurons for smiling. They 'understand the action' and induce the same sensation within you that is associated with smiling. You don't have to think about what the other person intends by this gesture. Your smile flows thoughtlessly and effortlessly in return.
Which brings us to yet another important curve- if mirror neurons are helping us to decode facial expressions and actions, then it stands to reason that those gifted people who are better at such complex social interpretations must be having a more active mirror neuron system.(Imagine your mom's strained smile coupled with the glint in her eye after you've just thrown a temper tantrum in front of a roomful of people...it promises dire retribution my friends. Trust me.)
Then does this mean that people suffering from disorders such as autism (where social interactions are difficult) have a dysfunctional or less than perfect mirror neuron system in some way?
Some scientists believe it to be so. They call it the 'broken mirror hypothesis', where they claim that malfunctioning mirror neurons may be responsible for an autistic individual's inability to understand the intention behind other people's gestures or expressions. Such people may be able to correctly identify an emotion on someone's face, but they wouldn't understand it's significance. From observing other people, they don't know what it feels like to be sad, angry, surprised or scared.
However, the jury is still out on this one folks. The broken mirror hypothesis has been questioned by others who are still skeptical about the very existence of these wonder neurons, or just how it is that these neurons alone suffered such a developmental hit when the rest of the autistic brain is working just dandy? Other scientists argue that while mirror neurons may help your brain to understand a concept, they may not necessarily ENCODE that concept. For instance, babies understand the meaning behind many actions without having the motor ability to perform them. If this is true, then an autistic person's mirror neurons are perfectly fine...they were just never responsible for his lack of empathy in the first place.
Slightly confused? Curious to find out more about these wunderkinds of the human brain? Join the club. Whether you're an passionate believer in these little fellas with their seemingly magical properties or still skeptical, let me add to your growing interest with one parting shot- since imitation appears to be the primary function of mirror neurons, they might well be partly responsible for our cultural evolution! How, you ask? Well, since culture is passed down from one generation to another through sharing, observation followed by imitation, these neurons are at the forefront of our lifelong learning from those around us. Research has found that mirror neurons kick in at birth, with infants just a few minutes old sticking their tongues out at adults doing the same thing.
So do these mirror neurons embody our humanity? Are they responsible for our ability to put ourselves in another person's shoes, to empathize and communicate our fellow human beings? That has yet to be determined. But after decades of research, one thing is for sure-these strange cells haven't yet ceased to amaze and we definitely haven't seen the last of them. To quote Alice in Wonderland, the tale keeps getting "curiouser and curiouser"!

This field of medicine requires much more physiological and pathophysiological knowledge than most people give it credit for. Psychiatric illness DO have physical manifestations of symptoms; in fact those symptoms help form the main criteria for differential diagnoses. For example, key physical symptoms of depression, besides having a low mood for more than two weeks (yes, two weeks is all it takes to be classified as 'depressed'), include fatigue, change in appetite, unexplained aches/pains, changes in menstrual cycle if you're a female, altered bowel habits, abnormal sleep, etc. Aside from this, studies suggest that psychiatric illnesses put you at higher risk for physical conditions including heart disease, osteoarthritis, etc. (the list really does go on)
Although some mental health conditions, like cognitive impairments, still do not have very effective treatment options; most psychiatric medications work very well, and are necessary for treating the patient. The stigma surrounding them by the public causes a huge problem for doctors. Many patients are reluctant to comply with medications because they are not as widely accepted as the ones for non-mental health conditions. A psychiatrist holds a huge responsibility for patient education. It can be tough to teach your patients about their medication, when many of them refuse to belief there is anything wrong with them (this is also because of stigma).
Contrary to my previous beliefs, psychiatrists DO NOT sit around talking about feelings all day. The stereotypical image of someone lying down on a couch talking about their thoughts/feelings while the doctor holds up ink blots, is done more in 'cognitive behavioural therapy.' While this is a vital healthcare service, it's not really what a psychiatrist does. Taking a psychiatric history is just like taking a regular, structured medical history; except you have to ask further questions about their personal history (their relationships, professional life, significant life events, etc), forensic history, substance misuse history (if applicable), and childhood/developmental history. Taking a psychiatric history for a new patient usually takes at least an hour.
The interesting thing about about treating a psychiatric patient is that the best guidelines you have for making them healthy is their personality before the symptoms started (this is called 'pre-morbid personality'). This can be difficult to establish, and can often be an ambiguous goal for a doctor to reach. Of course, there is structure/protocol for each illness, but each patient will be unique. This is a challenge because personalities constantly evolve, healthy or not, and the human mind is perpetual.
On top of this, whether mental or physical, a serious illness usually significally impacts a person's personality.
Most psychiatric conditions, while being very treatable, will affect the patient will struggle with for their whole life. This leaves the psychiatrist with a large portion of the responsibility for the patient's quality of life and well-being; this can be vey rewarding and challenging. The state of a person's mind is a perpetual thing, choosing the right medication is not enough.
Before I had done this rotation, I was quite sure that this was a field I was not interested in. I still don't know if it is something I would pursue, but I'm definitely more open-minded to it now!
PS: It has also taught me some valuable life lessons; most of the patients I met were just ordinary people who were pushed a little too far by the unfortunate combination/sequence of circumstances in their life. Even the ones who have committed crimes or were capable of doing awful things.. It could happen to anyone, and just because I have been lucky enough to not experience the things those people have, does not mean I am a better person for not behaving the same way as them.